Why Are Sastrugi a Problem for Antarctic Expeditions…

Coming back to the subject of sastrugi (just because it gives Ben nightmares!)… These aren’t soft snow ridges. They’re often rock-hard, jagged formations shaped by wind, earning the nickname “nature’s speed bumps.” When the sastrugi are small, pulks (sleds) can glide or bulldoze their way through them. But when they are larger—which they frequently are—they become one of the most exhausting and frustrating obstacles in polar travel.

Each sastrugi ridge can force you to drag a 100kg+ sled up and over or make wide detours. The surface between them is rarely smooth—just bumps, dips, and jerks. Ben recalls hours spent dragging his sled over what felt like a frozen washboard. The constant pounding wearing down both body and morale. Worse still, hard ridges can damage sled runners, twist ankles, or send pulks crashing sideways. Especially in flat light or whiteouts, when the ridges become almost invisible.

Historic explorers like Amundsen and Shackleton complained about the same thing. Dogs and men alike exhausted from the constant jolts and climbs. Even modern-day tractor traverses slow to a crawl in bad sastrugi fields. For us, it’ll all be human-powered, so we’ll need to watch every step and ridge.

Where We’ll Likely Encounter Sastrugi on Our Route

Sastrugi form wherever wind meets exposed snow—which is nearly everywhere in Antarctica. They’re especially prevalent in the high interior, sculpted by katabatic winds sweeping down from the Polar Plateau. The infamous 86–88°S stretch, on the approach to the South Pole, is known for vast sastrugi belts. Indeed, ALE also discuss the sastrugi in this area in their safety briefings! Ben certainly remembers the worst of them there. Though there were plenty of large, surprise patches of extremely large sastrugi at seemingly random points beforehand. At the same time, once Ben got into the the 88th degree and onto the plateau, they finally eased. Though never quite entirely disappeared….

While it is likely we will have some respite near the Pole on our route, sastrugi are going to be a near constant challenge for us. Berkner Island… The Filchner Ice Cap… The Support Force Glacier…? Yes. Sastrugi. From the top of the glacier to the plateau? Yup. And then on the other side of the Pole. Descending toward the Ross Ice Shelf. The Ross Ice Shelf itself… all open, wind-scoured snow, with plenty of opportunities for sastrugi to form.

In short, if there’s snow and wind, there’s sastrugi. And for much of our journey, they’ll be testing our endurance, patience, and ski- and pulk-repair skills.